1. Field of the Invention
The object of the invention is a device, a system and a method for measuring permeability, in particular permeability of a fibrin clot.
2. Description of the Related Art
Ischemia, a local blood supply disorder resulting from reduction or complete deficiency of blood supply in an organ or in a tissue caused by constriction or obstruction of its blood vessels, resulting in hypoxia, malnutrition and finally necrosis of the part of an organ suffering from ischemic process, is a frequent phenomenon in pathogenesis of many clinical conditions, as well as during performing surgical procedures. The causes of this phenomenon include, among others, formation of fibrin clots of abnormal stability and structure. Epidemiologic data obtained from ex vivo and in vitro studies indicate that the abnormal properties of fibrin clot are related to the occurrence of ischemic strokes, myocardial infarction or thromboembolic vascular disease. In general, the clots composed of dense network of thin fibrin fibres with tiny pores and high stability and resistance to enzymatic degradation, are related to the presence of prothrombotic state. Therefore, there are strong premises that the permeability of a fibrin clot can be a risk factor in the occurrence of thromboembolic events.
There are known methods for measuring permeability, for example by using Rowe's chamber. These methods involve assessing permeability and determining the coefficient of material permeability under a certain pressure of a flowing medium.
There is also known a device for assessing hydraulic permeability of hardening suspensions, described by FALACINSKI P., GARBULEWSKI K., KLEDYNSKI Z., SKUTNIK Z., ZIARKOWSKA A. 2004: “Badania barier hydraulicznych z zawiesin cementowo-bentonitowych z dodatkiem popiolów fluidalnych” (“Investigation of hydraulic barriers made of cement-bentonite suspensions with addition of fluidized ashes”), Przeglad Naukowy WIiKS, Yearbook XIII, Vol. 2/29, pp. 202-215.
The publication “A new optimized method for the determination of fibrin clot permeability” by Jonas A. Sjøland (Lippincott Williams & Wilkins, 2005, pp. 579-583) describes a system for measuring fibrin clot permeability, the system consisting of a glass vessel for fluid having a volume of 500 ml, equipped with a rubber stopper and a valve for levelling the pressure and a rubber hose connected to a polypropylene pipe (serologic pipette having the total volume of 1 ml, cut to a length allowing to fill it with 100 μl of material). The system is also equipped with a test tube (a receptacle), for collecting the fluid permeating through the fibrin clot and a stopwatch for measuring the permeation time. Use of such system requires a double measurement of the mass of the test tube—before and after the examination. Moreover, it is necessary to manually turn on and off the stopwatch, which is susceptible to the manual dexterity of the operator. Moreover, it is necessary to control the time lapse in order to stop collecting the permeate after a predetermined time (120 minutes to perfuse the clot and 110 minutes of measurement). A manual station requires the operator to monitor the level of a buffer in the tank due to its consumption, and weighing of the test tube used for the buffer permeated through the clot before and after the measurement. Thus, such measurement of permeability of a single clot is laborious and time consuming.
Besides, considering the fact that cardiovascular diseases are considered as the most frequent cause of death, and that the majority of diseases are related to the presence of prothrombotic state in blood vessels, there is a potential necessity to measure clot permeability as a routine test, which calls for utmost automation and simplification of the measurement.
Therefore, it would be advantageous to develop a method, a device and a system to automate and simplify the measurement of permeability, as well as to improve the quality of measurement.